Went for a 2:28 hr ride on Sunday and rode -19,802.87km! see https://connect.garmin.com/modern/activity/827607766
Individual route details were recorded as they are on Strava https://www.strava.com/activities/340653917 but interestingly, Strava thought I only rode 8,920.2km.
Any idea why it is wrong on Garmin?